骨髓间充质干细胞防护肾脏衰老的作用及其机制

背景：骨髓间充质干细胞具有分化成肾小管上皮细胞的功能，故推测，间充质干细胞可能具有治疗慢性肾功能减退的作用。 目的：研究骨髓来源的大鼠间充质干细胞防护肾脏衰老的作用及其可能的机制。 方法：实验建立衰老大鼠模型，尾静脉移植骨髓来源的大鼠间充质干细胞，应用荧光染料羟基荧光素二醋酸盐琥珀酰亚胺脂标记体外培养大鼠骨髓来源的间充质干细胞，将其回输肾脏衰老大鼠体内，应用荧光显微镜下观察间充质干细胞是否能够归巢于肾脏；全自动生化仪测定各组大鼠血清中尿素氮及肌酐水平变化；采用免疫荧光法，利用计算机图像叠加技术，观察蓝色荧光4’，6-二脒基-2-苯基吲哚分别与红色荧光的肾小管上皮细胞特异性蛋白-角蛋白的叠加情况。 结果与结论：骨髓来源的大鼠间充质干细胞能够归巢到衰老大鼠的肾脏。与衰老大鼠模型组相比，经过间充质干细胞生物治疗后的衰老大鼠血清中尿素氮及肌酐水平显著降低（P 〈0.05），肾脏组织可见少量4’，6-二脒基-2-苯基吲哚及异硫氰酸荧光素标记的角蛋白双染阳性细胞。结果显示，骨髓来源的大鼠间充质干细胞通过向肾小管上皮分化，这可能是其改善衰老大鼠肾脏的机制之一。

Effect and mechanism of mesenchymal stem cells on the aging kidney

BACKGROUND：Bone marrow mesenchymal stem cels can differentiate into renal tubular epithelial cels. It is speculated that mesenchymal stem cels may have a therapeutic role in chronic renal dysfunction.
OBJECTIVE： To study the effect of bone marrow mesenchymal stem cels on the aging kidney of rats and its possible mechanism.
METHODS： Aging models were established in rats. Rat bone marrow mesechymal stem cels cultured in vitro were labeled by 5,6-carboxyfluorescein diacetate, succinimidyl ester, and then injected into the ratsvia the tail vein. Under a fluorescence microscope, the cellhoming was observed. The contents of urea nitrogen and creatinine in serum of rats were tested by automatic biochemical analyzer. The overlaying of blue fluorescent 2-（4-amidinophenyl）-6-indolecarbamidine dihydrochloride and the specific protein of red fluorescent tubular epithelial cels （keratin protein） was detected by indirect immunofluorescence and computer image stacking technique.
RESULTS AND CONCLUSION： Bone marrow mesenchymal stem cels could arrive the kidney of rats. Compared with the model group, the contents of urea nitrogen and creatinine in serum were decreased in the treated group （P 〈 0.05）. The treated group showed a smal amount of double positive cels. These findings indicate that rat bone marrow mesenchymal stem cels may differentiate into renal tubular epithelial cels, which may be one of mechanisms that improve the aging kidney of rats.